The present disclosure relates to an exposure controller, an exposure control method, and an image pickup apparatus that variably control an aperture stop to obtain apodization effect.
A method in which an apodization filter whose transmittance is high at a middle part thereof and is gradually decreased toward a peripheral region is provided in an entrance pupil of an optical system, to improve contrast of an image is known. In addition, there is a method in which an aperture stop is variably controlled to obtain an effect (apodization effect) similar to the effect of the apodization filter. For example, in Japanese Unexamined Patent Application Publication No. Hei10-333202 (FIG. 2), a method in which an aperture stop is stopped down to a preset initial value at the start of an exposure period, and is gradually released during the exposure to obtain apodization effect is proposed.